The rise of sea levels has been studied by a number of scientific institutions and activist groups. Scientists and researchers have published hundreds of thousands of papers warning of the imminent threat rising sea levels pose. One of the more terrifying realizations is that due to the rise, millions and millions of people will be forced to leave their homes as coastal areas begin to disappear.
Over the years, scientists have made various attempts to estimate how many people will be affected by the encroaching waters. However, in a recent study published in the journal Nature Communications, researchers suggest that the previously estimated numbers are far too low.
The newly published study was conducted by climate scientists, Dr. Scott Kulp and Dr. Benjamin Strauss from the Climate Central organization based in New Jersey. Dr. Kulp and Dr. Strauss have determined that approximately 360 million people worldwide currently live in areas that are below the annual flood and high-tide lines. They also found that another 250 million people live just above these areas and are thus considered also to be gravely threatened by rapidly rising sea levels. This conclusion is three times more than any previously estimated figures.
"There is a really huge concentration of population density in the very lowest strips of land, in the lowest places along the coast globally," Strauss told Business Insider. "It turns out within those first couple of meters [above sea-level], there are more than 3 million people per vertical inch."
See a full table of global populations on land at risk here.
The scientists also note that even if society is able to stop the production of greenhouse emissions overnight, sea levels will still continue to climb and could rise an additional foot and a half by the year 2100. However, as that is nothing short of impossible, the likely rise is estimated to be as much as two to three feet within the next 80 years.
See permanent inundation surfaces predicted by Coastal Digital Elevation Models and NASA's Shuttle Radar Topography Mission sea level projection here.
In typical flood-risk assessments, scientists have been known to use data from NASA's Shuttle Radar Topography Mission, but according to Strauss, this system only uses the tops of buildings to determine elevation and not the actual ground. Therefore, the scientists used a different system. A system that was designed primarily to rectify that problem.
"We've elucidated that you can't measure flood risk by analyzing the elevation of rooftops - you have to know the height of the ground beneath your feet," Strauss said.
For their study, the pair of scientists examined data from 135 countries from all over the emissions spectrum. What they found was that people from Asia—primarily Indonesia—are "disproportionately threatened by this issue."
The study yielded another troubling estimation. According to Dr. Kulp and Dr. Strauss, 237 million people in Bangladesh, China, India, Indonesia, Thailand, and Vietnam are projected to experience hardships due to immense coastal flooding by 2050. That number could reach 250 million if emissions continue at the current rate through 2100.
The new estimates brought forth by this study only further accentuate the real threat that global warming and rising sea levels pose to coastal peoples and communities from all over the world. Strauss says that he hopes that the study's findings will motivate cities and countries to address that threat now.
